sooty necks

[zap]

I am shooting a 6.5x47 and am noticing some sooty necks. They have been reloaded around 5 times.

I read that sooty necks can come from the necks needing to be annealed, (they are not expanding to seal the chamber).

Is there some truth to this ?
And an even more important question is , if only some of my brass has sooty necks, could that contribute to accuracy problems ? (I have been struggling to get this rig to shoot).

 

[K22]

When I shoot H380 out of my 22 250 the necks are badly "sooted". It's not a dimensional issue with my rifle and casess since when I shoot Varget or IMR 4350 there is considerably less soot. In my case it's the nature of the powder.

I twist some 000 steel wool around the neck a few time then place in the tumble and they come out clean.

 

[fdshuster]

K22: You got it right. H380, H414, Winchester 748 & many other ball powders are the dirtiest out there. The amount of carbon on the fired case necks is a good indication of how much carbon is also in the bore.

I do find H335 to be one of the cleanest burning ( as verified with my borescope) ball powders & it does meter nicely in a drum measure. The only ball powder I will use.